The Florida Red Tide, caused by the harmful alga, Karenia brevis (formerly Gymnodinium breve) occurs annually along the Florida Gulf coast, and periodically throughout the northern Gulf of Mexico and along the US Atlantic coast, resulting in adverse economic and health effects. The alga is harmful because it produces a suite of neurotoxins (brevetoxins) that cause massive fish kills, contamination of shellfish (Neurotoxic Shellfish Poisoning) and results in respiratory problems and possibly additional health effects when people are exposed to the toxins in marine aerosol. The purpose of this Environmental Field Core (FC2) is to coordinate and implement collection and analysis of environmental data essential to implementation and interpretation of the field-oriented Research Projects. These include FC1, toxin probes and assays, RP1, Characterization of Brevetoxin Aerosols (Cheng) , and RP4, Epidemiology of red Tide Exposure (Fleming). Support will be in the form of: 1) monitoring the Florida Gulf coast, in the Sarasota region, for red tide blooms to alert project participants to possible field study opportunities, 2) maintenance of field collecting equipment and supplies, coordination of deployment and calibration of sampling equipment for field studies, 3) coordination and implementation of sampling protocol, including sample chain of custody, sample transport and processing, and interlaboratory calibration of analytical instrumentation, 4) Sample collection and analysis of brevetoxins in air and water by LC-MS, and Karenia brevis cell counts, 5) Sample collection and transport to UNCW (FC1) for total brevetoxin analysis by ELISA, and for culture and identification of new Karenia species. 6) Collaboration with Project Managers for data interpretation and dissemination of results, including report and manuscript preparation. Environmental sample collection will follow the protocol of Pierce et al. (2005). Seawater samples will be collected in 1-L bottles for cell counts and brevetoxin analyses 3 times daily. Marine aerosol will be collected with 8 high-volume samplers, placed in a grid of 200m x 50m, AM and PM, to assess aerosolized toxin concentrations over time and space. FC2 will coordinate with RP1 and RP4 for deployment of particle-size impactors, to assess the particle size of toxin-containing aerosol to which subjects are exposed. FC2 also will assist RP1 and RP4 in deploying a portable weather station to monitor meteorological conditions. Brevetoxin content will be determined by high performance liquid chromatography interfaced with mass spectrometry (LCMS) analyses. In addition, water samples will be collected during red tide blooms along the southwest Florida coast for exposure to asthmatic sheep by RP3 (Project by Abraham), and for identification and isolation of different species of Karenia by FC1, to determine the incident of different Karenia species and to identify the toxins produced by the different species. FC2 will coordinate field deployment and air and water sample collection and analyses for the beach studies and the subsequent 5-day, follow-up exposure studies, in cooperation with FC1, RP1 and RP4. Results from FC1 LC-MS analyses of brevetoxins in marine aerosol during beach and sub-acute residential exposure studies will be used to provide realistic exposure concentrations and duration for collaborative laboratory studies undertaken by RP2 and RP3.